decoction, decocture 1. The extraction of an essence or active ingredient from a substance by boiling. 2. A concentrated substance that results from decoction, or boiling. 3. Water in which a crude vegetable drug has been boiled and which therefore contains the constituents or principles of the substance soluble in boiling water. 4. The act or p... Found on http://www.wordinfo.info/words/index/info/view_unit/516/